The morphology core provides support for all sections of the renal center by providing for the routine processing of cells and tissues as well as morphologic and morphometric interpretation. Included in this core are facilities for the sectioning and processing of frozen tissue and cells for immunohistochemistry including immunoperoxidase and immunofluorescence. In addition, this core also provides for the processing and analysis of paraffin embedded tissue for light microscopy including special strains. Last, but not least, the core provides for routine processing and analysis of tissues and cells by ultrastructural (EM) analysis. If applicable, quantitative morphometric analysis is also done. Historically, the morphology core of the renal center has received heavy usage with several hundred samples submitted each year from all sections of the center. We anticipate that this heavy usage will continue and in fact increase. For example, we project that for the first year of the renewal period that 155 frozen sections will be processed; 825 samples processed for light microscopy, and 535 specimens for EM analysis. Thus, as can be appreciated, the morphology core provides an essential service for all the investigators in the renal center.